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Digital Needle: Ripping vinyl records with a scanner (2013)

cs.huji.ac.il

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Re: Digital Needle: Ripping vinyl records with a scanner (2013)

#41

Post by dr_zoidberg »

MrsPeaches wrote: post #11
Hfjfjdjfjceijfj wrote: post #8

Stero channels aren't encoded in the depth and radial axes. They're encoded in the same plane, but rotated 45 degrees, so a mono record player (depth only) plays a balanced sum of each channel. Edit: mono is radial only, not depth.

For anyone else who was intrigued by this, I found this helpful animation: https://www.vinylrecorder.com/stereo.html

When I read the title I immediately thought of a "laser tip" that and reading the reflections of it, not something based on software that would "read" an an image.

Following this animation I'm left thinking that you could do a bit of filtering to better extract the wave(s) from an image, though you'd require a particular setup for the lighting conditions to get the best possible quality out of it. And then back to my first idea: probably a laser-tip would be the best tool here too.

Unfortunately I don't have vinyl records around to test any of this!

Re: Digital Needle: Ripping vinyl records with a scanner (2013)

#42

Post by elevaet »

blackearl wrote: post #21
geocrasher wrote: post #14

These are so wonderfully distorted . I am getting somewhere between the signal in the movie "Contact" and whispers of the hive mind of the Borg. Amazing sounds, even if they aren't true to the recording.

You might like The Caretaker. It's less about the music itself and more about how your mind and memories slowly deteriorate with age https://en.wikipedia.org/wiki/The_Caretaker_(musician)

Hauntology!

Re: Digital Needle: Ripping vinyl records with a scanner (2013)

#43

Post by bluGill »

dehrmann wrote: post #20
philjohn wrote: post #10

Earlier quoted context omitted.

The funky EQ is the RIAA curve[1] - by essentially rolling off the bass and boosting the treble you can fit more on a disc, it attenuates some of the clicks and pops and is kinder on the vinyl and needle. It's trivial to invert in software, and as another response points out, there is indeed a working laser record player - although the record needs to be extensively cleaned before playback or it doesn't work very wel…

This is part of what people hear when they say "vinyl sounds better."

There are one of several things.

Most likely, CDs just don't get mastered right. The music is compressed and so even though the format is better, the music is worse. Vinyl is sold to people who care about sound, in their living rooms so they get better mastering. Digital is for people out and about, in your car you need compression even though it destroyes the music you can't even hear 3/4ths of the sound without it. This isn't the fault of the format, but the result remains, digital music is objectively worse.

Vinyl is able to get a slightly better S/N ratio in perfect conditions. So if the record is new it might be better (every time you play the record you wear it just a bit). Odds are it isn't, as almost nothing has enough dynamic range for this to matter.

They are used to worse sound and prefer it. CDs are perfect - vinyl often introduces imperfections that people like to hear. By objective measurements the music isn't perfect, but they like that imperfection.

Most likely it is the first. It is by far the most significant difference.

Re: Digital Needle: Ripping vinyl records with a scanner (2013)

#44

Post by dylan604 »

TylerE wrote: post #29
voldacar wrote: post #9

Earlier quoted context omitted.

not cheap, but yeah it works great. https://www.elpj.com/ I actually got to hear one once. Extremely neutral and high-res, but the record has to be super clean because with the laser, you will hear every little speck of dust. Also it doesn't work with colored vinyl, iirc. edit: they use 5 different lasers to get the data out of the groove, go read the section on their site, it's actually really intricate and cool > t…

Noise is also a big part of the RIAA curve. Almost all the noise on a record is high frequency...so by applying a strong treble rolloff most of it just disappears.

Sounds like DolbyNR for cassettes. What high hats?

Re: Digital Needle: Ripping vinyl records with a scanner (2013)

#45

Post by dmje »

geocrasher wrote: post #14

These are so wonderfully distorted . I am getting somewhere between the signal in the movie "Contact" and whispers of the hive mind of the Borg. Amazing sounds, even if they aren't true to the recording.

Yeh. Thinking they'd make a pretty rad segment in an ambient track

Re: Digital Needle: Ripping vinyl records with a scanner (2013)

#46

Post by andrewzah »

bluGill wrote: post #43
dehrmann wrote: post #20

Earlier quoted context omitted.

This is part of what people hear when they say "vinyl sounds better."

There are one of several things. Most likely, CDs just don't get mastered right. The music is compressed and so even though the format is better, the music is worse. Vinyl is sold to people who care about sound, in their living rooms so they get better mastering. Digital is for people out and about, in your car you need compression even though it destroyes the music you can't even hear 3/4ths of the sound without it.…

"Vinyl is able to get a slightly better S/N ratio in perfect conditions."

No. Compact Discs have an SNR of 96dB. Vinyl typically has an SNR of 60-70dB. The physics of these mediums aside, CDs are a newer technology... Why would we have gone for inferior distribution mediums?

"Most likely, CDs just don't get mastered right. The music is compressed and so even though the format is better, the music is worse"

Compression like that has more to do with radio play + the genre of music. Thankfully, the loudness wars are mostly over, but generally speaking the actual distributed master would've been the same.

"This isn't the fault of the format, but the result remains, digital music is objectively worse."

Please provide such objective citations. Mixing and mastering engineers do their best to make music that sounds good on a variety of audio systems. When I worked in a studio, we would mix on $8k genelec monitors, some cheaper monitors, and also test the mix in our cars and on our phones. Part of the art and difficulties in that was producing a mix that sounded good on great to average systems, and passable/decent on like mono phone speakers. Music and music hardware has never been more accessible than today, so I find it hard to believe that everyone a few decades ago had such amazing systems compared to today.

"Vinyl is sold to people who care about sound"

Citation needed. There are people who just want vinyl because it looks cool (especially the colored limited releases), and they go play it on a $50 Victrola all-in-one. There are CD enthusiasts who have systems worth > $200k.

"CDs are perfect - vinyl often introduces imperfections that people like to hear."

This is totally subjective. A CD is a bit-for-bit perfect representation of what the author wanted to distribute. The actual things like "warmth" that people talk about depend much more on the pre-amplifier, amplifier, and speakers.

There is nothing wrong with liking LPs (I collect them myself), but they are in no way, shape, or form better than the bit-for-bit perfect distribution of CDs (that also don't degrade every time you play one).

Re: Digital Needle: Ripping vinyl records with a scanner (2013)

#48

Post by h2odragon »

andrewzah wrote: post #37
Yaa101 wrote: post #34

Earlier quoted context omitted.

I found out when digitizing vinyl that LP's before 1977, when digital mixing and mastering was not the norm that there is more data in the frequencies between 20 and 50kHz. I do my recording standard at 192kHz and analogue LP's often reach 48kHz of data while digital mastered ones do only 22kHz. After that date often the frequency is cutoff at 20-22kHz, probably to save memory room. Only after 2000-2010 there is enou…

"Most awful are cds having only 16 bits and 41kHz sample rate, by modern standards really poor." 44.1kHz is all that one needs for -perfect fidelity-, given that humans cannot hear higher than ~20kHz. See: Nyquist-Shannon Sampling Theorem. [0] 16 bits of quantization gives a Signal to Noise Ratio (SNR) of 96dB, and noise dithering increases that [1]. More bits are not necessary unless one is doing music production wi…

Some humans can hear much higher than 20khz. Very little of our recording and playback equipment does well above that point, however, so efforts to reproduce that part of the spectrum most often fail miserably.

CD's are certainly good enough for now.

Re: Digital Needle: Ripping vinyl records with a scanner (2013)

#49

Post by Yaa101 »

andrewzah wrote: post #37
Yaa101 wrote: post #34

Earlier quoted context omitted.

I found out when digitizing vinyl that LP's before 1977, when digital mixing and mastering was not the norm that there is more data in the frequencies between 20 and 50kHz. I do my recording standard at 192kHz and analogue LP's often reach 48kHz of data while digital mastered ones do only 22kHz. After that date often the frequency is cutoff at 20-22kHz, probably to save memory room. Only after 2000-2010 there is enou…

"Most awful are cds having only 16 bits and 41kHz sample rate, by modern standards really poor." 44.1kHz is all that one needs for -perfect fidelity-, given that humans cannot hear higher than ~20kHz. See: Nyquist-Shannon Sampling Theorem. [0] 16 bits of quantization gives a Signal to Noise Ratio (SNR) of 96dB, and noise dithering increases that [1]. More bits are not necessary unless one is doing music production wi…

I am doing production with these recordings, tools are more precise at higher bit and sample rates. Also quality of listening equipment is a factor as hearing is not a flat frequency response, things as ambiance and resonance play a role, music is not a single frequency tone but a combination of complicated frequency additions, subtractions, multiplications and divisions. So more frequency room can produce nicer highs and clearer sound, especially when music is uncompressed. It is simplistic to state that 44.1/16bit is enough, if that is the case then any combination of recording, amplifier and speaker would suffice. This just isn't the case, also that we would need awesome priced equipment isn't really worth it. But there really is a difference between a phone with a music app playing a 16bit/44.1kHz song on a medium quality headphones and a dedicated player with a good DAC chip playing a 96kHz song on a good quality headphones. People that cannot hear the difference should not invest in such equipment and will be happy with the need to invest less money for their entertainment.

Re: Digital Needle: Ripping vinyl records with a scanner (2013)

#50

Post by voldacar »

Syzygies wrote: post #40
voldacar wrote: post #9

Earlier quoted context omitted.

not cheap, but yeah it works great. https://www.elpj.com/ I actually got to hear one once. Extremely neutral and high-res, but the record has to be super clean because with the laser, you will hear every little speck of dust. Also it doesn't work with colored vinyl, iirc. edit: they use 5 different lasers to get the data out of the groove, go read the section on their site, it's actually really intricate and cool > t…

Slide/negative scanners use multiple passes and depth perception to cleanly ignore dust on film. I'm surprised that this wasn't part of ELP's spec to the engineers. A giant fail if they can't even remove this noise in post-processing.

There's no AD step in the ELP. it's an analog system from the laser to the line out. So there's no way to do multiple passes while listening to the record, though you can adjust the depth in the groove that the laser scans.
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